概述

Math.log2() 函数返回一个数字以 2 为底的对数.

语法

Math.log2(x)

参数

x
任意数字.

描述

如果传入的参数小于 0, 则返回 NaN.

示例

Math.log2(2)     // 1
Math.log2(1024)  // 10
Math.log2(1)     // 0
Math.log2(0)     // -Infinity
Math.log2(-2)    // NaN
Math.log2("1024")// 10
Math.log2("foo") // NaN

规范

Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
Math.log2		 Standard Initial definition.

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